The Rolls-Royce Pegasus, formerly the Bristol Siddeley Pegasus, is a British

turbofan The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft engine, aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which ac ...

engine originally designed by

Bristol Siddeley Bristol Siddeley Engines Ltd (BSEL) was a British aero engine manufacturer. The company was formed in 1959 by a merger of Bristol Aero-Engines Limited and Armstrong Siddeley Motors Limited. In 1961 the company was expanded by the purchase of t ...

. It was manufactured by

Rolls-Royce plc Rolls-Royce Holdings plc is a British multinational aerospace and defence company incorporated in February 2011. The company owns Rolls-Royce, a business established in 1904 which today designs, manufactures and distributes power systems for ...

. The engine is not only able to power a

jet aircraft A jet aircraft (or simply jet) is an aircraft (nearly always a fixed-wing aircraft) propelled by jet engines. Whereas the engines in propeller-powered aircraft generally achieve their maximum efficiency at much lower speeds and altitudes, jet ...

forward, but also to direct

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...

downwards via swivelling nozzles. Lightly loaded aircraft equipped with this engine can manoeuvre like a

helicopter A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attribu ...

. In particular, they can perform vertical takeoffs and landings. In US service, the engine is designated F402. The unique Pegasus engine powers all versions of the Harrier family of multi-role

military aircraft A military aircraft is any Fixed-wing aircraft, fixed-wing or rotorcraft, rotary-wing aircraft that is operated by a legal or insurrectionary armed service of any type. Military aircraft can be either combat or non-combat: * Combat aircraft are ...

. Rolls-Royce licensed

Pratt & Whitney Pratt & Whitney is an American aerospace manufacturer with global service operations. It is a subsidiary of Raytheon Technologies. Pratt & Whitney's aircraft engines are widely used in both civil aviation (especially airlines) and military av ...

to build the Pegasus for US built versions. However Pratt & Whitney never completed any engines, with all new build being manufactured by Rolls-Royce in Bristol, England. The Pegasus was also the planned engine for a number of aircraft projects, among which were the prototypes of the German Dornier Do 31 VSTOL military transport project.

Development

Background

Michel Wibault Michel Henri Marie Joseph Wibault (born 5 June 1897, died 23 January 1963) was a French aircraft designer. He was a strong advocate of metal construction, and his airliners were important in the development of French commercial aviation in the 1 ...

, the French aircraft designer, had the idea to use vectored thrust for vertical take-off aircraft. This thrust would come from four centrifugal blowers shaft driven by a

Bristol Orion The Bristol Orion aero engine was a two-shaft turboprop intended for use in later marks of the Bristol Britannia and the Canadair CL-44. Although the engine was built and underwent a development program, the BE.25 Orion project was cancelled i ...

turboprop A turboprop is a turbine engine that drives an aircraft propeller. A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. ...

, the exhaust from each blower being vectored by rotating the blower scrolls. Although the idea of vectoring the thrust was quite novel, the engine proposed was considered to be far too heavy. As a result, an engineer at

Bristol Engine Company The Bristol Aeroplane Company, originally the British and Colonial Aeroplane Company, was both one of the first and one of the most important British aviation companies, designing and manufacturing both airframes and aircraft engines. Notable a ...

, Gordon Lewis, began in 1956 to study alternative engine concepts, using, where possible, existing engine components from the

Orpheus Orpheus (; Ancient Greek: Ὀρφεύς, classical pronunciation: ; french: Orphée) is a Thracian bard, legendary musician and prophet in ancient Greek religion. He was also a renowned poet and, according to the legend, travelled with J ...

and

Olympus Olympus or Olympos ( grc, Ὄλυμπος, link=no) may refer to: Mountains In antiquity Greece * Mount Olympus in Thessaly, northern Greece, the home of the twelve gods of Olympus in Greek mythology * Mount Olympus (Lesvos), located in Le ...

engine series. The work was overseen by the Technical Director

Stanley Hooker Sir Stanley George Hooker, CBE, FRS, DPhil, BSc, FRAeS, MIMechE, FAAAS, (30 September 1907 – 24 May 1984) was a mathematician and jet engine engineer. He was employed first at Rolls-Royce where he worked on the earliest designs such as ...

. One concept which looked promising was the BE52, which initially used the Orpheus 3 as the engine core and, on a separate coaxial shaft, the first two stages of an Olympus 21 LP compressor, which acted as a fan, delivering compressed air to two thrust vectoring nozzles at the front of engine. At this point in the design exercise, the exhaust from the LP turbine discharged through a conventional rear nozzle. There were separate intakes for the fan and core compressor because the fan did not supercharge the core compressor. Although the BE.52 was a self-contained power plant and lighter than Wibault's concept, the BE.52 was still complicated and heavy. As a result, work on the BE.53 concept started in February 1957. In the BE.53 the Olympus stages were fitted close to the Orpheus stages; thus simplifying the inlet ducting. The Olympus stages now supercharged the Orpheus core, improving the overall pressure ratio, creating what is now considered a conventional turbofan configuration. For a year Bristol designed the engine in isolation, with little feedback from the various airframe manufacturers furnished with data. However, in May 1957 the team received a supportive letter from Sydney Camm of

Hawker Aviation Hawker Aircraft Limited was a British aircraft manufacturer that was responsible for some of the most famous products in British aviation history. History Hawker had its roots in the aftermath of the First World War, which resulted in the bank ...

stating they were looking for a

Hawker Hunter The Hawker Hunter is a transonic British jet-powered fighter aircraft that was developed by Hawker Aircraft for the Royal Air Force (RAF) during the late 1940s and early 1950s. It was designed to take advantage of the newly developed Rolls-Ro ...

replacement. The aircraft designer,

Ralph Hooper Ralph Spenser Hooper, OBE, FREng, FRAeS (30 January 1926 – 12 December 2022) was an English aeronautical engineer, recognised mostly for his work on the Hawker Siddeley Harrier, specifically in relation to the marriage between the Pegasus eng ...

, suggested having the four thrust vectoring nozzles (originally suggested by Lewis), with hot gases from the rear two. Further joint discussions helped to refine the engine design. The

1957 Defence White Paper The 1957 White Paper on Defence (Cmnd. 124) was a British white paper issued in March 1957 setting forth the perceived future of the British military. It had profound effects on all aspects of the defence industry but probably the most affected w ...

, which focused on missiles, and not manned aircraft – which were declared 'obsolete' - was not good news, because it precluded any future government financial support for development of not already extant manned combat aircraft. This prevented any official financial support for the engine or aircraft from the

Ministry of Defence {{unsourced, date=February 2021 A ministry of defence or defense (see spelling differences), also known as a department of defence or defense, is an often-used name for the part of a government responsible for matters of defence, found in state ...

. Fortunately, engine development was financially supported to the tune of 75% from the Mutual Weapons Development Program, Verdon Smith of Bristol Siddeley Engines Limited (BSEL), which Bristol Engines had by then become on its merger with

Armstrong Siddeley Armstrong Siddeley was a British engineering group that operated during the first half of the 20th century. It was formed in 1919 and is best known for the production of luxury vehicles and aircraft engines. The company was created following t ...

, quickly agreeing to pay the remainder. The first prototype engine (one of two BE53/2s built), ran on 2 September 1959 and featured a 2-stage fan and used the Orpheus 6 core. Although the fan was overhung, inlet guide vanes were still incorporated. The HP spool comprised a 7-stage compressor driven by a single stage turbine. A 2-stage LP turbine drove the fan. There was no plenum at fan exit, but 4 thrust vectoring nozzles were fitted. Further development of the engine then proceeded in tandem with the aircraft, the

Hawker P.1127 The Hawker P.1127 and the Hawker Siddeley Kestrel FGA.1 are the British experimental and development aircraft that led to the Hawker Siddeley Harrier, the first ''vertical and/or short take-off and landing'' ( V/STOL) jet fighter-bomber. Deve ...

. The aircraft first flew (tethered hover) on 21 October 1960, powered by the BE53/3 (Pegasus 2). Free hover was achieved on 19 November of the same year. Transition to wing-borne flight occurred in 1961. Later versions of the P.1127 were fitted with the Pegasus 3 and eventually the Pegasus 5. The Pegasus 5 was also used in the

Kestrel The term kestrel (from french: crécerelle, derivative from , i.e. ratchet) is the common name given to several species of predatory birds from the falcon genus ''Falco''. Kestrels are most easily distinguished by their typical hunting behaviou ...

, a refinement of the P.1127, of which nine were built for a Tripartite evaluation exercise. The Kestrel was subsequently developed into the Harrier combat aircraft. By the time the Pegasus 5/2 was built, both the fan and HP compressor had been

zero-stage Jet engines and other gas turbine engines are often uprated by adding a zero-stage, sometimes written '0' stage, to the front of a compressor.Hooker, Sir Stanley (1984). ''Not much of an Engineer'', P. 153. Airlife Publishing Ltd, Shrewsbury, Eng ...

d and 2nd stage added to the HP turbine.

Testing and production

The flight testing and engine development received no government funding; the plane's funding came entirely from Hawker. The first engines had barely enough thrust to lift the plane off the ground due to weight growth problems. Flight tests were initially conducted with the aircraft tethered, with the first free hover achieved on 19 November 1960. The first transition from static hover to conventional flight was achieved on 8 September 1961. It was originally feared that the aircraft would have difficulty transitioning between level and vertical flight, but during testing it was found to be extremely simple. Testing showed that because of the extreme power to weight ratio it only took a few degrees of nozzle movement to get the aircraft moving forward quickly enough to produce lift from the wing, and that even at a 15 degree angle the aircraft accelerated very well. The pilot simply had to move the nozzle control forward slowly. During transition from horizontal back to vertical the pilot would simply slow to roughly 200 knots and turn the nozzles downward, allowing the engine thrust to take over as the aircraft slowed and the wings stopped producing lift. The RAF was not much of a convert to the VTOL idea, and described the whole project as a ''toy'' and a ''crowd pleaser''. The first prototype P1127 made a very heavy landing at the Paris Air Show in 1963. Series manufacture and design and development improvement to the Pegasus to produce ever higher thrusts were continued by Bristol engines beyond 1966, when Rolls-Royce Ltd bought the Company. A related engine design, the 39,500 lbf (with reheat)

Bristol Siddeley BS100 The Bristol Siddeley BS.100 is a British twin-spool, vectored thrust, turbofan aero engine that first ran in 1960. The engine was designed and built in limited numbers by Bristol Siddeley Engines Limited. The project was cancelled in early 1 ...

for a supersonic VTOL fighter (the Hawker Siddeley P.1154) was not developed to production as the aircraft project was cancelled in 1965. To date, 1,347 engines have been produced and two million operating hours have been logged with the Harriers of the

Royal Air Force The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) an ...

(RAF),

Royal Navy The Royal Navy (RN) is the United Kingdom's naval warfare force. Although warships were used by English and Scottish kings from the early medieval period, the first major maritime engagements were fought in the Hundred Years' War against Fr ...

U.S. Marine Corps The United States Marine Corps (USMC), also referred to as the United States Marines, is the maritime land force service branch of the United States Armed Forces responsible for conducting expeditionary and amphibious operations through co ...

and the navies of

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area, the List of countries and dependencies by population, second-most populous ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

Spain , image_flag = Bandera de España.svg , image_coat = Escudo de España (mazonado).svg , national_motto = '' Plus ultra'' (Latin)(English: "Further Beyond") , national_anthem = (English: "Royal March") , ...

and

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...

. A non-vectored 26,000 lb thrust derivative of the Pegasus running on

liquid hydrogen Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below its critical point of 33 K. However, for it to be in a fully l ...

, the RB.420, was designed and offered in 1970 in response to a NASA requirement for an engine to power the projected

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program n ...

on its return flight through the atmosphere. In the event, NASA chose a shuttle design using a non-powered gliding return.

Design

The Pegasus vectored-thrust turbofan is a two-shaft design with three low pressure (LP) and eight high pressure (HP) compressor stages driven by two LP and two HP

turbine A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced by a turbine can be used for generating ...

stages respectively. It is the first turbofan to have the fan ahead of the LP shaft front bearing. This eliminated the requirement for bearing-support struts in front of the fan and the icing hazard that goes with them. Unusually the LP and HP spools rotate in opposite directions which significantly reduces the gyroscopic effects which would otherwise cause aircraft control problems at low aircraft speeds. LP and HP blades are made from titanium. The fan is a transonic design and airflow is 432 lb/s. The engine employs a simple

thrust vectoring Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the ve ...

system that uses four swiveling nozzles, giving the Harrier thrust both for lift and forward propulsion, allowing for

STOVL A short take-off and vertical landing aircraft (STOVL aircraft) is a fixed-wing aircraft that is able to take off from a short runway (or take off vertically if it does not have a heavy payload) and land vertically (i.e. with no runway). The ...

flight. Combustion system is an annular combustor with ASM low-pressure vaporising burners. Engine starting was by a top-mounted packaged combined gas turbine starter/ APU.

Nozzles

The front nozzles, which are made of steel, are fed with air from the LP compressor, and the rear nozzles, which are of

Nimonic Nimonic is a registered trademark of Special Metals Corporation that refers to a family of nickel-based high-temperature low creep superalloys. Nimonic alloys typically consist of more than 50% nickel and 20% chromium with additives such as titani ...

with hot (650 °C) jet exhaust. The airflow split is about 60/40 front/back. The nozzles are rotated using motorcycle chains driven by air motors powered by air from the HP compressor. The nozzles rotate through a range of 98.5 degrees.

Position of the engine

The engine is mounted in the centre of the Harrier and as a result, it was necessary to remove the wing to change the powerplant after mounting the fuselage on trestles. The change took a minimum of eight hours, although using the proper tools and lifting equipment this could be accomplished in less than four.

Water injection

The maximum take-off thrust available from the Pegasus engine is limited, particularly at the higher ambient temperatures, by the turbine blade temperature. As this temperature cannot reliably be measured, the operating limits are determined by jet pipe temperature. To enable the engine speed and hence thrust to be increased for take-off, water is sprayed into the combustion chamber and turbine to keep the blade temperature down to an acceptable level. Water for the injection system is contained in a tank located between the bifurcated section of the rear (hot) exhaust duct. The tank contains up to 500 lb (227 kg, 50 imperial gallons) of distilled water. Water flow rate for the required turbine temperature reduction is approximately 35gpm (imperial gallons per minute) for a maximum duration of approximately 90 seconds. The quantity of water carried is sufficient for and appropriate to the particular operational role of the aircraft. Selection of water injection engine ratings (Lift Wet/Short Lift Wet) results in an increase in the engine speed and jet pipe temperature limits beyond the respective dry (non-injected) ratings (Lift Dry/Short Lift Dry). Upon exhausting the available water supply in the tank, the limits are reset to the 'dry' levels. A warning light in the cockpit provides advance warning of water depletion to the pilot.

Variants

; Pegasus 1 (BE53-2): The two prototype engines were demonstrator engines which developed about on the test bed. Neither engine was installed in a P.1127. ; Pegasus 2 (BE53-3): Used in the initial P.1127s, ; Pegasus 3: Used on the P.1127 prototypes, ; Pegasus 5 (BS.53-5): Used for the

Hawker Siddeley Kestrel The Hawker P.1127 and the Hawker Siddeley Kestrel FGA.1 are the British experimental and development aircraft that led to the Hawker Siddeley Harrier, the first ''vertical and/or short take-off and landing'' (V/STOL) jet fighter-bomber. Develo ...

evaluation aircraft at ; Pegasus 6 (Mk.101): For initial production Harriers at , first flown in 1966 and entered service 1969 ; Pegasus 10 (Mk.102): For updating first Harriers with more power and used for the AV-8A, , entering service in 1971. ; Pegasus 11 (Mk.103): The Pegasus 11 powered the first generation Harriers, the RAF's

Hawker Siddeley Harrier The Hawker Siddeley Harrier is a British military aircraft. It was the first of the Harrier series of aircraft and was developed in the 1960s as the first operational ground attack and reconnaissance aircraft with vertical/short takeoff an ...

GR.3, the

USMC The United States Marine Corps (USMC), also referred to as the United States Marines, is the maritime land force service branch of the United States Armed Forces responsible for conducting expeditionary and amphibious operations through co ...

AV-8A and later the Royal Navy's Sea Harrier. The Pegasus 11 produced and entered service in 1974. ; Pegasus 14 (Mk.104): Navalised version of the Pegasus 11 for the Sea Harrier, same as the 11 but some engine components and castings made from corrosion-resistant materials. ; Pegasus 11-21 (Mk.105 / Mk.106): The 11-21 was developed for the second generation Harriers, the USMC

AV-8B Harrier II The McDonnell Douglas (now Boeing) AV-8B Harrier II is a single-engine ground-attack aircraft that constitutes the second generation of the Harrier family, capable of vertical or short takeoff and landing (V/STOL). The aircraft is primari ...

and the

BAE Harrier II The British Aerospace Harrier II is a second-generation vertical/short takeoff and landing (V/STOL) jet aircraft used previously by the Royal Air Force (RAF) and, between 2006 and 2010, the Royal Navy (RN). The aircraft was the latest developm ...

s. The original model provided an extra . The RAF Harriers entered service with the 11-21 Mk.105, the AV-8Bs with F402-RR-406. Depending on time constraints and water injection, between (max. continuous at 91% RPM) and (15 s wet at 107% RPM) of lift is available at sea level (including splay loss at 90°).AV-8B Standard Aircraft Characteristics
''US Naval Air Systems Command'', October 1986. Retrieved: 16 April 2010. The Mk.106 development was produced for the

Sea Harrier FA2 The British Aerospace Sea Harrier is a naval short take-off and vertical landing/ vertical take-off and landing jet fighter, reconnaissance and attack aircraft. It is the second member of the Harrier family developed. It first entered servic ...

upgrade and generates . ; Pegasus 11-61 (Mk.107): The 11-61 (aka -408) is the latest and most powerful version of the Pegasus, providing .Pegasus - Power for the Harrier
''RR website'', 2004. Retrieved: 17 April 2010. This equates to up to 15 percent more thrust at high

ambient temperature Colloquially, "room temperature" is a range of air temperatures that most people prefer for indoor settings. It feels comfortable to a person when they are wearing typical indoor clothing. Human comfort can extend beyond this range depending on ...

s, allowing upgraded Harriers to return to an

aircraft carrier An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a ...

without having to dump any unused weapons which along with the reduced maintenance reduces total cost of engine use. This latest Pegasus is also fitted to the AV-8B+. The RAF/RN was in the process of upgrading its GR7 fleet to GR9 standard, initially through the Joint Upgrade and Maintenance Programme (JUMP) and then through the Harrier Platform Availability Contract (HPAC). All GR7 aircraft were expected to have been upgraded by April 2010. Part of this process was the upgrade of the Mk.105 engines to Mk.107 standard. These aircraft were known as GR7As and GR9As.

Applications

BAE Sea Harrier The British Aerospace Sea Harrier is a naval short take-off and vertical landing/ vertical take-off and landing jet fighter, reconnaissance and attack aircraft. It is the second member of the Harrier family developed. It first entered servic ...

* Dornier Do 31 *

Hawker Siddeley P.1127 The Hawker P.1127 and the Hawker Siddeley Kestrel FGA.1 are the British experimental and development aircraft that led to the Hawker Siddeley Harrier, the first ''vertical and/or short take-off and landing'' (V/STOL) jet fighter-bomber. Develo ...

;Intended application *

Armstrong Whitworth AW.681 The Armstrong Whitworth AW.681, also known as the Whitworth Gloster 681 or Hawker Siddeley HS.681, was a projected United Kingdom, British long-range STOL military transport aircraft design of the early 1960s. Developed by manufacturer Armstr ...

Engines on display

Pegasus engines are on public display at the following museums: *

Imperial War Museum Duxford Imperial War Museum Duxford is a branch of the Imperial War Museum near Duxford in Cambridgeshire, England. Britain's largest aviation museum, Duxford houses the museum's large exhibits, including nearly 200 aircraft, military vehicles, artill ...

Royal Air Force Museum London The Royal Air Force Museum London (also commonly known as the RAF Museum) is located on the former Hendon Aerodrome. It includes five buildings and hangars showing the history of aviation and the Royal Air Force. It is part of the Royal Air Fo ...

* Cranfield University, England *

Science Museum (London) The Science Museum is a major museum on Exhibition Road in South Kensington, London. It was founded in 1857 and is one of the city's major tourist attractions, attracting 3.3 million visitors annually in 2019. Like other publicly funded ...

National Naval Aviation Museum The National Naval Aviation Museum, formerly known as the National Museum of Naval Aviation and the Naval Aviation Museum, is a military and aerospace museum located at Naval Air Station Pensacola, Florida. Founded in 1962 and moved to its cur ...

Pensacola, Florida *

Naval Aviation Museum (India) The Naval Aviation Museum is a military aviation museum located in Bogmalo, from Vasco da Gama, Goa, India focused on the history of the Indian Naval Air Arm. The museum is divided into two main parts, an outdoor exhibit and a two-storey in ...

, Goa, India *

Deutsches Museum The Deutsches Museum (''German Museum'', officially (English: ''German Museum of Masterpieces of Science and Technology'')) in Munich, Germany, is the world's largest museum of science and technology, with about 28,000 exhibited objects from ...

, Munich, Germany *

Rolls-Royce Heritage Trust, Allison, Indianapolis, Indiana Rolls-Royce (always hyphenated) may refer to: * Rolls-Royce Limited, a British manufacturer of cars and later aero engines, founded in 1906, now defunct Automobiles * Rolls-Royce Motor Cars, the current car manufacturing company incorporated i ...

Rolls-Royce Heritage Trust Collection
(Derby)
Airworld Aviation Museum, Caernarfon, Wales, UK

Specifications (Pegasus 11-61)

References

;Citations ;Bibliography * Pegasus: the Heart of the Harrier, Andrew Dow, Pen & Sword, * ''Not Much of an Engineer'', Sir Stanley Hooker, Airlife Publishing, * Powerplant: Water Injection System, Aircraft Engineering and Aerospace Technology, Vol. 42 Iss: 1, pp: 31–32. DOI: 10.1108/eb034594 (Permanent URL). Publisher: MCB UP Ltd

External links

* ttp://www.flightglobal.com/pdfarchive/view/1972/1972%20-%202773.html "Designing the Pegasus"a 1972 ''Flight'' article by

Bill Gunston Bill Gunston (1 March 1927 – 1 June 2013) was a British aviation and military author. He flew with Britain's Royal Air Force from 1945 to 1948, and after pilot training became a flying instructor. He spent most of his adult life doing resear ...

"Pegasus Updating Prospects"
a 1977 ''Flight'' article on improvements to the Pegasus

Video clips

''Brits Who Made The Modern World'' August 2008 ''Five''

King's College, London
{{USAF gas turbine engines Low-bypass turbofan engines

Pegasus Pegasus ( grc-gre, Πήγασος, Pḗgasos; la, Pegasus, Pegasos) is one of the best known creatures in Greek mythology. He is a winged divine stallion usually depicted as pure white in color. He was sired by Poseidon, in his role as hor ...

1959 introductions 1950s turbofan engines